Regional ecosystem details for 11.4.3
| Regional ecosystem | 11.4.3 |
|---|---|
| Vegetation Management Act class | Endangered |
| Wetlands | Contains Palustrine |
| Biodiversity status | Endangered |
| Subregion | 33, 26, 30, 34, 29, 4.4, (32), (31), (28), (24), (27), (6.4), (10), (11), (35), (22), (16), (18), (15), (36), (19), (21), (17), (6.2), (20) |
| Estimated extent1 | Pre-clearing 1647000 ha; Remnant 2021 83000 ha |
| Short description | Acacia harpophylla and/or Casuarina cristata shrubby open forest on Cainozoic clay plains |
| Structure code | Open Forest |
| Description | Acacia harpophylla and/or Casuarina cristata open forest. Acacia harpophylla forms a continuous canopy with varying densities of Casuarina cristata, forming part of the canopy or emerging above it. Casuarina cristata may be dominant or form pure stands particularly in the south of the bioregion (subregions 33, 36). Eucalyptus spp. such as E. orgadophila, E. populnea, E. microcarpa, Eucalyptus woollsiana, E. cambageana and E. thozetiana (on shallower soils and upper slopes) may be scattered through the canopy or occur as emergents. Brachychiton rupestris may also be present in places. An open to dense, tall shrub layer is present, and is dominated by Eremophila mitchellii and/or Geijera parviflora. Low shrubs are often present, occasionally forming a distinct layer dominated by species such as Carissa ovata and Alectryon diversifolius. Melaleuca bracteata may be present in low-lying areas. The ground layer is sparse to open, and composed of grasses and forbs. Occurs on Cainozoic clay plains with cracking clay soils which are often with a weak gilgai microrelief. The plains may be flat to gently undulating. Soils are often cracking clay which are usually deep to very deep, often self-mulching, and sometimes with surface stone. Texture contrast soils and other clays may also be present in places. Contains Palustrine. (BVG1M: 25a). Vegetation communities in this regional ecosystem include: 11.4.3a: Melaleuca squamophloia woodland associated with Acacia harpophylla communities. May include scattered occurrences of other tree species such as Eucalyptus tereticornis, E. populnea, Acacia harpophylla and Casuarina cristata. In some instances E. tereticornis dominates with other species restricting to a narrow fringe. There may be an understorey of Damasonium minus, Typha orientalis, Cyperus spp., and other wetland plants associated with ephemeral wetlands. Associated with heavy dark clay soils with very broad and deep gilgai which is seasonally ponded and remain wet for long periods. Palustrine. (BVG1M: 25a). 11.4.3b: Eucalyptus argophloia, Acacia harpophylla open forest. Associated trees may include Casuarina cristata, Eucalyptus populnea or Eucalyptus microcarpa, with a shrub layer of Geijera parviflora. Associated with heavy dark clay soils with very broad and deep gilgai which is seasonally ponded and remain wet for long periods. Not a Wetland. (BVG1M: 25a). |
| Supplementary description | Speck et al. (1968), Wandoan (10); Dawson (1972), Tara, Hopelands, Humbug; Galloway et al. (1974), LU 38, 58; Vandersee (1975), Dalby (4); Mullins (1980), Tara, Sedgley; Neldner (1984), 6 (124); Fensham and Fairfax (1997), 3 |
| Protected areas | Southwood NP, Erringibba NP, Bendidee NP, Bunya Mountains NP, Lake Broadwater CP |
| Special values | 11.4.3: Specific habitat for threatened flora species including Xerothamnella herbacea (Endangered) and Eucalyptus argophloia (Vulnerable) and Jalmenus eubulus, pale imperial hairstreak butterfly (Eastwood et al. 2008). Larger gilgai may provide ephemeral wetland habitat. 11.4.3a: Provides important wetland habitat. 11.4.3b: Larger gilgai may provide ephemeral wetland habitat. |
| Fire management guidelines | INTERVAL: Fire return interval not relevant. INTERVAL_MIN: 100. INTERVAL_MAX: 100. STRATEGY: Maintain fire management of surrounding country so that wildfires will be very limited in extent. Frequent fire at the edge of this RE keeps fuel loads low. Protection from fire is necessary. ISSUES: Casuarina cristata is fire sensitive, although germination can be good in bare areas. Brigalow is soft-seeded, so germination is not promoted by fire. Buffel grass invasion will increase risk from fire. High intensity fires will cause damage to overstorey. Grazing may be an option for reducing fuel loads where exotic grass such as buffel have invaded. |
| Comments | 11.4.3: Areas of this regional ecosystem that occur on texture contrast and/or sodic soils often have lower (12 metres) canopy and sparse to absent mid-layer. Widespread in the southern half of the bioregion. Extensively cleared for cropping and pasture. Naturalised species associated with this regional ecosystem include *Malvastrum americanum. 11.4.3a: Occurs at Bellevue swamp and other scattered locations within a much larger area of Acacia harpophylla +/- Casuarina cristata (RE 11.4.3). Mainly occurs scattered across brigalow clay plains in subregions 27, 30 and 31. 11.4.3b: Confined to a small area to the west of Durong, N. of Chinchilla. This regional ecosystem has been almost completely cleared, and exists primarily as regrowth or isolated paddock trees of Eucalyptus argophloia. |
1 Estimated extent is from version 13 pre-clearing and 2021 remnant regional ecosystem mapping. Figures are rounded for simplicity. For more precise estimates, including breakdowns by tenure and other themes see remnant vegetation in Queensland.
